1. Field of the Invention
The invention relates generally to military tactical aircraft oxygen mask bayonet and bayonet receiver assemblies. More particularly, it relates to an apparatus for reducing the risk of parachute riser entanglement with the oxygen mask bayonet and bayonet receiver in the event of ejection.
2. Description of the Prior Art
The ejection from an aircraft during an emergency subjects the pilot to various torso loads. These loads must be considered in the design, implementation and deployment of parachutes for the pilots during the emergency ejection scenario. In addition, the type of aircraft and the corresponding ejection schedule must also be considered in order to assure safety during parachute deployment. Thus, the deployment of the parachute and corresponding riser and shroud lines in the emergency ejection situation has proven to be a significant design aspect of the entire pilot helmet and oxygen mask connection thereto.
By way of example, the Harrier Aircraft (AV-8B) has an ejection seat configuration that is unlike all other fixed wing pilot ejection seats. The AV-8B ejection schedule includes a low altitude high acceleration that subjects the pilot to higher than normal torso loads. It has been demonstrated that for all ranges of air speeds, the parachute riser lines are sure to contact the side of the pilot helmet during deployment. This riser contact is not subtle, rather it typically manifests itself as xe2x80x9criser slapxe2x80x9d, a known condition that subjects the pilot to unsafe and possibly fatal head and neck forces.
Referring to the prior art FIGS. 1-3, there is shown an exemplary helmet 10 having a visor 12 and other operational equipment mounted thereon. The oxygen mask strap holder 14, which is attached to the oxygen mask (not shown) via straps 15a and 15b, includes an oxygen mask bayonet 16 that is releasably inserted into a bayonet receiver 30 mounted onto the respective sides of the helmet 10. The bayonet 16 includes a bayonet tab 18, ratchet-like pawls 19a and 19b and a distal end 20. During operation, end 20 is inserted into opening 32 in bayonet receiver 30, and ratchet pawls 19a and 19b engage corresponding notches (not shown) within receiver 30 to adjustably lock the position of the connected oxygen mask with respect to the helmet and onto the pilots face. Generally, there are four (4) positions or clicks that bayonet 16 can make when inserted into bayonet receiver 30. These four (4) positions determine how tightly the oxygen mask is positioned on the pilot""s face and enable pilot adjustment of the same.
The bayonet receiver 30 includes two mounting holes 34a and 34b that receive screws from the underside of the helmet. In order to release the oxygen mask, the pilot simply pulls down on bayonet tab 18 (in the direction of the arrow in FIG. 2), thereby releasing pawls 19a and 19b from their engagement within receiver 30 and causing the bayonet to slide out of the receiver.
Unfortunate accidents have resulted in a reconsideration of the oxygen mask bayonet 16 and bayonet receiver 30 configuration on the pilot""s helmet. It has been determined that during ejection and parachute deployment, the riser and shroud lines can get caught or hung up on any one of the bayonet tab 18, the bottom edges 36 of bayonet receiver 30 and/or the aft end 20 of bayonet 16 that protrudes beyond receiver 30 (FIG. 3). These potential hang up hazards are on both sides of the helmet and thereby create the potential for a fatality during ejection. It is also possible that the riser and shroud lines could cause inadvertent release of one of the bayonets during ejection, thereby increasing the risk of injury and/or fatality to the air crew during ejection.
It is therefore desirable to retrofit the existing oxygen mask bayonet and bayonet receiver with a deflector that eliminates the potential for riser entanglement with the bayonet and/or bayonet receiver during ejection and parachute deployment.
It is therefore an object of the present invention to provide a universal deflector for the oxygen mask bayonet and bayonet receiver for pilot helmets of various sizes.
It is another object of the invention to provide a universal deflector for the oxygen mask bayonet and bayonet receiver that is easily installed and replaced for both new and retrofit applications.
It is yet another object of the invention to provide a universal deflector for the oxygen mask bayonet and bayonet receiver that does not require re-tooling of the existing bayonet and bayonet receiver assemblies.
These and other objects are achieved in accordance with an embodiment of the invention wherein a bayonet receiver deflector is disposed on the helmet between the bayonet receiver and helmet, and a bayonet deflector is connected to the oxygen mask bayonet. The bayonet receiver deflector includes a contoured side for providing a smooth transition between the helmet and the bayonet receiver on at least one side of the bayonet receiver, and means for securing the bayonet receiver deflector to the helmet. The oxygen mask bayonet deflector is made of two parts consisting of a bayonet ramp deflector and a bayonet tab deflector. The bayonet ramp deflector includes a ramped side and a bayonet tab portion and means for connecting the deflector to the oxygen mask bayonet. The bayonet tab portion includes a slot in an upper side thereof and an opening in a rear side thereof aligned with a hole in the bayonet tab.
The bayonet tab deflector is generally frusto-conical in shape and includes a stem and a notch on the stem. In order to secure the bayonet tab deflector to the ramped deflector, the stem passes through a hole in the bayonet tab and into the opening in the rear side of the bayonet tab portion of said bayonet ramp deflector. An e-clip or other releasable clip engages the notch in the stem from through the opening in the bayonet tab portion of the bayonet ramped deflector and secures the tab deflector to the bayonet ramp deflector by sandwiching the bayonet tab between the two parts.
Other objects and features of the present invention will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. It should be further understood that the drawings are not necessarily drawn to scale and that, unless otherwise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein.